#include <bits/stdc++.h>
#define ll long long
#define PI acos(-1)
#define M(n, m) memset(n, m, sizeof(n));
const int INF = 1e9 + 7;
const int maxn = 1e5;
using namespace std;

int main()
{
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
    return 0;
}
